Full-time QA Engineer @ NexusMD (AI Healthcare)
✨ Open to Senior SDET & AI Reliability Roles (Melbourne / Remote)

Hi, I'm Jack Hao.
Senior QA Engineer & AI Reliability Specialist

Bridging 5+ years of enterprise software testing & financial systems (Citibank, WMS) with modern AI agent evaluation, prompt robustness fuzzing, and end-to-end test automation (Playwright, Pytest, Jest).

Melbourne & Bendigo, VIC, Australia
5+ Years
Enterprise Software & QA Testing
NexusMD
Full-Time QA @ AI Healthcare
3+ Tools
Production Tools & Web Apps (PromptHavoc, MockHavoc, PTE RS)
M.Sc. + B.S.
IoT (La Trobe) & Software Engineering

AI QA Tooling & Production Projects

Specialized developer tools for AI prompt robustness fuzzing, chaos API testing, and full-stack software.

🎙️ Interactive EdTech & Speech Tool 🚀 80+ Users in 48h

PTE RS Trainer

PTE Repeat Sentence Shadowing & Audio Memory Retention System

Independently engineered to solve personal PTE prep hurdles: short-term auditory memory decay, long-sentence forgetting, and shadowing stutter. Built from real user pain points into an intuitive tool, organically attracting 80+ active test-takers within 48 hours of launch.

🧠 Sense-group slicing & variable-speed shadow reading engine
🎯 Word-by-word alignment & real-time pronunciation diagnosis
🚀 Pain-point to product: validated by 80+ organic users in first 48 hours
React / TypeScript Web Speech & Audio API Audio Chunking TailwindCSS Vercel
🎨 Multimodal Vision AI Full-Stack App

AI Art Gallery

Curated Multimodal Vision AI & Art Intelligence Platform

An immersive virtual gallery powered by multimodal LLM integration. Features serverless Edge Functions invoking vision-language models to analyze brushstroke nuances, authenticate artistic schools, and automatically generate museum-grade bilingual curatorial commentary.

🤖 Real-time Multimodal LLM vision analysis for brushstroke, style & period appraisal
📜 Automated bilingual museum-grade curatorial critique & exhibition placard generation
🔍 Interactive high-res magnifier inspection with Supabase Edge backend & cloud storage
Multimodal LLM Vision API Supabase Edge Functions Image Compression Bilingual AI
⚡ AI Security & QA Studio Production Live

PromptHavoc

AI Agent & Prompt Robustness Fuzzing Studio

Stress-test system prompts against jailbreaks, adversarial prompt injections, system prompt extraction, and JSON format drift. Features automated 0–100 vulnerability scoring and instant generation of automated evaluation test suites.

🛡️ Red-teaming fuzzing engine for LLM system prompts
📊 Real-time vulnerability grading & drift detection
🧪 Auto-exports Playwright & Promptfoo eval suites
React / TypeScript LLM Evals Prompt Injection Fuzzing Playwright CodeGen TailwindCSS Vercel
⚡ API Chaos & Contract Studio Production Live

MockHavoc

AI Edge-Case & API Contract Assertion Studio

Converts any standard API JSON response into chaos-mutated edge-case payloads (type corruption, null injections, boundary overflows, latency injection). Instantly compiles production-grade Playwright, Jest, Pytest, and Zod contract test assertions.

💥 Deterministic chaos mutations (Null/Type drift/Overflow)
Instant Zod Schema & API Contract validation generator
📝 One-click export to Pytest, Jest, and Playwright suites
TypeScript Contract Testing Zod Schemas Pytest / Jest / Playwright Chaos Mutation Engine
🏥 Current Enterprise Focus Active Full-Time

NexusMD AI Healthcare Testing Architecture

Clinical Workflow Reliability & Multimodal RAG Evals

Designing RAG evaluation frameworks and deterministic regression suites for AI clinical workflows. Measuring answer faithfulness, source attribution accuracy, and multimodal LLM response consistency under strict HIPAA standards.

AI Healthcare RAG Evaluation Faithfulness & Grounding LLM Guardrails API Integration HIPAA/Privacy QA

5+ Years of Engineering & QA Impact

Demonstrated track record spanning AI healthcare startups, high-concurrency supply chain systems, and global banking transactions.

QA Engineer

NexusMD AI Healthcare
2026 — Present Melbourne, Australia (Full-Time)
  • Lead end-to-end quality assurance and automated testing strategies for AI-powered clinical diagnostic & medical workflow platforms.
  • Architect automated RAG evaluation frameworks measuring Faithfulness, Context Precision, and Source Attribution to suppress hallucination and ensure evidence-grounded responses.
  • Design prompt robustness fuzzing, hallucination guardrails, and deterministic API contract regression suites to prevent defects in clinical data handling.
AI Healthcare QA RAG Evaluation Faithfulness & Grounding LLM Guardrails Playwright API Contract Testing Python

Senior Software Tester

Hangzhou Dahiti Network Technology Co., Ltd.
Jun 2020 — Apr 2022 Hangzhou, China
  • Spearheaded quality engineering and SQL data validation for enterprise Warehouse Management Systems (WMS) processing high-volume inventory transactions.
  • Constructed complex SQL reconciliation test scripts to guarantee 100% data integrity across order dispatch, picking wave lists, and inventory double-checks.
  • Developed automated functional test suites, reducing regression cycle times by 40% and preventing critical discrepancies in logistics dispatching.
SQL Data Validation WMS Architecture Automated Testing Data Integrity API Testing

Software Tester / QA Engineer

Zhejiang Merit Interactive Network Technology (GeTui)
Apr 2016 — Mar 2019 Hangzhou, China
  • Executed automated and manual test suites across Android & iOS SDKs and push notification backend systems handling billions of daily messages.
  • Analyzed distributed system logs and message queues to troubleshoot delivery latencies, device connectivity failures, and push notification throughput bottlenecks.
  • Collaborated directly with core mobile SDK development teams to verify data analytics tracking, user engagement feeds, and client-side stability.
Push Notification Systems Mobile QA (Android/iOS) Distributed Log Analysis SDK Verification

Quality Analyst

Pactera Technology International Citibank APAC Project
Aug 2015 — Apr 2016 Shanghai, China
  • Authored and executed comprehensive test plans for Citibank APAC core banking transaction platforms under stringent financial regulatory standards.
  • Conducted rigorous multi-currency transaction, account settlement, and regulatory compliance testing in collaboration with cross-regional engineering teams.
  • Identified critical edge cases in transaction handling, ensuring zero defects reached production in mission-critical financial systems.
Banking Core Systems Transaction Testing Financial Compliance APAC Cross-border QA

Modern Tech Stack & Quality Matrix

From modern AI robustness testing and automated contract validation to cloud infrastructure and enterprise databases.

🛡️

AI Evals & Prompt Security

LLM Robustness & Red Teaming

RAG Evals & Faithfulness Prompt Injection Fuzzing LLM Vulnerability Scoring Jailbreak Defense Testing AI Agent Evals System Prompt Extraction Hallucination Guardrails

Test Automation & SDET

End-to-End & Chaos Testing

Playwright Pytest Jest API Contract Testing (Zod) Chaos Mutation Engine Postman / Newman Regression Test Architectures
💻

Languages & Database

Backend & Verification

Python SQL (Complex Queries & Validation) TypeScript / JavaScript Java HTML5 / CSS3 PostgreSQL / MySQL
☁️

Cloud, DevOps & IoT

Infrastructure & Deployment

AWS (EC2, S3, Lambda, IoT Core) GitHub Actions CI/CD Docker Linux / Shell Scripting Vercel & Cloudflare MQTT / IoT Protocols

Education & Industry Certifications

Formal degrees in Internet of Things and Software Engineering, complemented by accredited cloud and cybersecurity certificates.

🎓 Degrees & Academics

Master of Internet of Things

2024 — 2025
La Trobe University, Victoria, Australia

Specialized in Cloud IoT Architectures, IoT Protocols, Distributed Data Mining, Database Fundamentals, and Scalable Backend Platforms.

Bachelor of Software Engineering

2011 — 2015
Hubei University of Economics, China

Comprehensive foundation in Computer Science, Data Structures & Algorithms, Java Software Architecture, Database Systems, and Network Security.

📜 Professional Certifications

Google Cybersecurity Professional Certificate

Google / Coursera • Security Auditing, Network Defense, Python Automation

AWS Academy Cloud Foundations

Amazon Web Services • Cloud Architecture, IAM, Serverless, S3/EC2/VPC

Google IT Support Professional Certificate

Google • Networking, Systems Administration, Operating Systems & Security

Let's Connect

Let's Build Reliable Software Together

Currently working full-time at NexusMD and always happy to discuss AI quality engineering, test automation frameworks, SDET challenges, or potential collaboration in Australia & worldwide.

📍 Based in Victoria, Australia • Available for Hybrid/Remote roles